Modern integrated circuits often include millions or even billions of semiconductor devices, such as transistors, diodes, and capacitors, among others. To help integrated circuit designers arrange these devices on the final integrated circuit, electronic design automation (EDA) software tools have been developed. These EDA tools, which often have a computer aided design (CAD) interface, can help designers arrange devices and verify whether a given arrangement of devices is in accordance with a manufacturer's fabrication rules. By providing designers with a flexible CAD interface where design changes are relatively quick and easy to implement, EDA tools help to ensure that integrated circuits, when actually manufactured, function as envisioned by a designer. This disclosure relates to improved EDA tools.